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71.
S D Hwang N Midorikawa P Punnarak Y Kikuchi H Kondo I Hirono T Aoki 《Journal of fish diseases》2012,35(12):927-934
RNA aptamers are artificial nucleic acids that specifically bind to a wide variety of targets. They are an effective tool for pharmaceutical research and development of antiviral agents. Here, we describe four Hirame rhabdovirus (HIRRV)‐RNA aptamers (H1, H2, H3 and H4) that we obtained from an in vitro process called the systematic evolution of ligands by exponential enrichment (SELEX). The HIRRV‐RNA aptamers specifically bind to HIRRV. Hirame natural embryo (HINAE) cells treated with virus and the RNA aptamer showed a decrease in appearance of cytopathic effect when compared with control (treated only with virus). Rhodovulum sulfidophilum was transformed with genes for the RNA aptamers, and the aptamers were detected in the culture medium, indicating that they were secreted from the cells. Thus, the recombinant R. sulfidophilum might be a powerful tool for the prevention of HIRRV in aquaculture. 相似文献
72.
Md. Abdul Kader Shunsuke Koshio Manabu Ishikawa Saichiro Yokoyama Mahbuba Bulbul Binh Thanh Nguyen Jian Gao Asda Laining 《Aquaculture Research》2012,43(10):1427-1438
An experiment was carried out to evaluate fermented soybean meal and squid by‐product blend (1:1) (FP) as replacement of fishmeal (FM) for Japanese flounder, Paralichthys olivaceus. Five isocaloric (19 kJ g?1) diets were prepared by replacing 0 (FP0), 12 (FP12), 24 (FP24), 36 (FP36) and 48% (FP48) FM protein with FP. Triplicate groups of juveniles (mean weight of 3.9 g) were delivered the test diets for 8 weeks in a flow‐through sea water system. The results showed that there were no significant differences (P > 0.05) among the growth rates of fish fed FP0, FP12, FP24 and FP36 diets. Growth and nutrient utilization parameters were significantly reduced in fish fed FP48 diet. Although, whole body proximate composition of fish were not significantly affected by the dietary treatments compared to the control; methionine and phenylalanine contents were significantly decreased in FP48 group. Protein retention was also significantly decreased in the similar group of fish. Dietary treatments did not alter most of the plasma metabolites, while some of the health parameters were improved in the replacement groups. Results suggested that FP is a potential candidate for alternative protein ingredient in aquafeed and can replace 36% FM protein in the diet of Japanese flounder. 相似文献
73.
Mike Greenblatt Christopher L. Brown Michael Lee Silvia Dauder Howard A. Bern 《Fish physiology and biochemistry》1989,6(5):261-278
Developmental profiles of thyroxin (T4), triiodothyronine (T3) and radioactive iodide uptake were established for eggs and T4 and T3 profiles were established for larvae (whole-body, yolk-only and body-only) of coho and chinook salmon. T4 and T3 were consistently present in all samples. In eggs, hormone levels remained fairly constant in all cohorst for at least the first three weeks of incubation, but then fluctuated in both directions in some sample groups. Large increases in T4 (from 9 ng/g to 245 ng/g) were seen in 1985 chinook eggs 28 days after fertilization. Radioactive iodide uptake (which was used as a possible indicator of thyroxinogenesis) increased at least 10-fold in both 1986 coho and chinook eggs from 23–30 days after fertilization. T4 (62 ng/g) and T3 (393 ng/g) were found in the bodies of 28-day-old 1986 chinook embryos. In whole larvae, hormone levels varied depending upon the cohort studied. In general, initial body-only concentrations of both T4 and T3 decreased as body weight increased, but before yolksac resorption was completed, both thyroid hormone content and concentration increased (except for chinook T3). T4 and T3 content in larval yolk stayed constant as yolksac size decreased, resulting in increased thyroid hormone concentration in the yolksac. All of these data suggest that the initial source of thyroid hormones in coho and chinook salmon eggs is maternal, but that by approximately 3–4 weeks after fertilization, the developing embryos begin to produce their own thyroid hormones. After hatching, increases in tissue T4 and T3 concentration coupled with constant T4 and T3 content in diminishing yolksacs suggest that larvae also produce their own thyroid hormones; yolksac content then may reflect both the original maternal hormones and the larva-producted hormones. 相似文献
74.
采用冷浸法按溶剂与植物干粉6:1体积比对大蒜、葱、韭菜和辣椒4种植物样品浸泡提取.在提取物浓度为l g/mL下,测定了各提取物对玉米蚜的忌避效果.结果表明:辣椒、大蒜的不同溶剂提取物对玉米蚜均表现出较好的忌避作用.辣椒乙醚提取物对玉米蚜的忌避效果最佳,忌避率平均为0.64;其次忌避效果较好的为大蒜丙酮提取物,忌避率平均为0.62.忌避效果较低的为葱乙醚提取物,忌避率仅为0.25. 相似文献
75.
76.
灌溉水矿化度及盐分带入量对小麦相对产量影响的统计分析 总被引:1,自引:0,他引:1
在搜集、统计大量咸水灌溉试验资料的基础上,选取咸水充分灌溉条件下矿化度和小麦产量的完整对应数据103组,统计分析了灌溉水矿化度及单位面积盐分带入量对小麦相对产量的影响,结果表明,随着灌溉水矿化度的增加,小麦相对产量呈线性递减趋势,当矿化度大于1.0 g/L时,灌溉水矿化度每增加1 g/L,小麦减产约5.6%;与矿化度类似,随着单位面积盐分带入量的增加,小麦的相对产量也线性降低,盐分带入量每增加1000 kg/hm2,小麦的产量将减少约2%。进一步的检验结果显示,应用灌溉水矿化度及单位面积盐分带入量均可较为可靠地估算小麦的相对产量,估算相对误差基本可控制在16%以内。 相似文献
77.
Renate Kvingedal Brad S. Evans Joseph J.U. Taylor Jens Knauer Dean R. Jerry 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):23-28
To understand the influence the environment and associated genotype by environment interactions will exert on future silver-lip pearl oyster (Pinctada maxima) selective breeding programs, this study assessed the relative performance in four shell growth traits of spat from five full-sib families, when spat were communally reared at different salinities (29, 34 and 40 ppt), food availability (high, medium and low), food quality (high, medium and low), and in a hatchery vs. ocean environment for 43 days.Rearing environment was found to influence growth expression, with significant differences evident when oysters were grown at different salinities in the ocean instead of hatchery, or when fed algae of differing nutritional quality. As indicated by MANOVA, family comparative growth performances were also altered when the environment changed, with significant environment by family interactions apparent in the food quality, food availability and hatchery vs. ocean rearing treatments. Changes in salinity, however, did not affect relevant family performances.These results indicate that growth and relative family performance in P. maxima may change dependent on local environmental conditions and that genotype by environment effects may need to be considered in breeding programs for this species. 相似文献
78.
由于绿棋楠沉香是公认的顶级沉香,近年来市场出现大规模的人工栽培绿棋楠沉香,但目前缺乏科学的鉴定依据及精准的质量分级指标,阻碍了绿棋楠沉香功能性产品的开发及拓展。以22批次的惠东绿棋楠沉香为研究对象,结合外观及构造特征、乙醇提取物含量和化学成分分析,研究惠东绿棋楠的特点。结果显示,结香时间为10~18个月的惠东绿棋楠油脂含量丰富,其乙醇提取物在21.45%~53.12%之间,平均值为41.10%,这为绿棋楠的质量分级提供了依据;惠东绿棋楠乙醇提取物中的主要成分为2-(2-苯乙基)色酮类化合物,占其总含量的47.72%~99.29%,是惠东绿棋楠中重要的化学成分,可作为惠东绿棋楠的鉴定依据。 相似文献
79.
80.
利用纤维素生物质资源生产燃料乙醇是纤维素类物质工业转化的一个重要方面。本文对国内外纤维燃料乙醇生产中的重要工艺。如原料预处理、纤维素水解、五碳糖与六碳糖发酵等研究情况进行了综述。并对国内外产业化情况进行了介绍。 相似文献